Summary of the invention
Main purpose of the present invention is, for above-mentioned deficiency of the prior art, provides a kind of signal deteching circuit relevant based on Geordie and method.
The present invention solves the technical scheme that prior art problem adopts: a kind of signal deteching circuit relevant based on Geordie, comprise two comparator arrays, subtracter array, two multiplier arrays, two adder trees, a divider and a register;
Signal x1 ... xn, y1 ... yn sends into corresponding comparator, subtracter array simultaneously respectively, wherein signal x1 ... xn's n has walked abreast
2secondary compare operation, i.e. sgn (xi-xj), wherein (i, j=1 ... n), signal y1 ... yn's n has walked abreast
2secondary compare operation and subtraction operation, i.e. sgn (yi-yj) and yi-yj, wherein (i, j=1 ... n), above course synchronization carries out, and n is signal length;
The comparison obtained, subtraction result sends into corresponding multiplier array simultaneously, synchronously completes n respectively
2secondary parallel 2 input multiply operation, i.e. sgn (xi-xj) (yi-yj) and sgn (yi-yj) (yi-yj), wherein (i, j=1 ... n);
The multiplication result obtained sends into corresponding adder tree simultaneously, synchronously completes n respectively
2the parallel addition operation of individual input, namely
With
Wherein (i, j=1 ... n);
The addition results obtained is sent in 2 input dividers, completes
wherein (i, j=1 ... n);
The correlation result obtained is sent in register.
Further, comparator, subtracter array are the matrix (n is signal length) of a n × n, and each element on matrix is made comparisons computing and subtraction respectively; Multiplier array is n
2the multiplier of individual 2 inputs; Adder tree is a n
2the adder of individual input; Divider completes 2 input division arithmetics; The result of related operation deposited by register.
Based on the signal detecting method that Geordie is relevant, comprise step:
S1, signal x1 ... xn, y1 ... yn sends into corresponding comparator, subtracter array simultaneously respectively, wherein signal x1 ... xn's n has walked abreast
2secondary compare operation, i.e. sgn (xi-xj), wherein (i, j=1 ... n), signal y1 ... yn's n has walked abreast
2secondary compare operation and subtraction operation, i.e. sgn (yi-yj) and yi-yj, wherein (i, j=1 ... n), above course synchronization carries out, and n is signal length;
The comparison that S2, step S1 obtain, subtraction result sends into corresponding multiplier array simultaneously, synchronously completes n respectively
2secondary parallel 2 input multiply operation, i.e. sgn (xi-xj) (yi-yj) and sgn (yi-yj) (yi-yj), wherein, (i, j=1 ... n);
The multiplication result that S3, step S2 obtain sends into corresponding adder tree simultaneously, synchronously completes n respectively
2the parallel addition operation of individual input, namely
with
Wherein (i, j=1 ... n);
The addition results that S4, step S3 obtain is sent in 2 input dividers, completes
Wherein (i, j=1 ... n);
The correlation result that S5, step S4 obtain is sent in register.
The invention has the beneficial effects as follows: when containing impulsive noise composition in ambient noise, matched filter and product moment correlation coefficient lost efficacy substantially, and Geordie is correlated with shows its splendid robustness in containing the noise circumstance of pulse repetition, comprises very close to mathematic expectaion and the less standard deviation of actual value.Which illustrating that Geordie is correlated with is a kind of effective tool carrying out input in containing the environment of impulse noise interference, and has splendid performance advantage compared with the method generally used at present.
Embodiment
Describe technical scheme of the present invention in detail below with reference to drawings and the specific embodiments, so as clearer, understand invention essence of the present invention intuitively.
Input is a substance of signal transacting, and echo-signal time delay detection and signal of communication synchronization acquistion are again radar, sonar and the requisite link of modern communication technology.The present invention be directed to the judgement that existing convectional signals time delay detection technique cannot overcome the interference effect input that signal brings due to the impulsive noise be added in the air well to propose.Matched filter can make the signal passed through obtain maximum signal to noise ratio and export SNR=2E
s/ N
0(wherein E
sfor input useful signal energy, N
0/ 2 is the bilateral power spectral density of additive white Gaussian noise), and under this standard as optimum linear filter and obtain applying the most widely in signal lag detects.But the Theoretical Proof process for its performance is assumptions' environment noise is simple additive white Gaussian noise, and often can include impulse noise component in the ambient noise of reality.Now, in certain hour, signal to noise ratio can decline to a great extent, and then has a strong impact on the performance of matched filter.From the angle of correlation analysis, the problem of evaluated error that classical coefficient correlation also exists paired pulses noise-sensitive and brings because not making full use of effective information.Geordie is correlated with can by utilizing the interference being reduced noise by the rank information of the signal of noise pollution, and the data value information simultaneously making full use of clean signal avoids the loss of effective information to reduce evaluated error.Therefore Geordie is correlated with and is incorporated into signal transacting field and effectively can solves signal lag test problems under impulsive noise background as a kind of means of input.And obtaining the relevant one of Geordie expression-form of equal value by deriving, based on this expression formula, proposing a kind of structural design of FPGA counting circuit.
Concrete, defined function H (t), as t>0, H (t)=1; When t≤0, H (t)=0.Then have respectively P and Q in (1) formula:
Sign function Sgn (t), works as t>0, Sgn (t)=1; Work as t=0, Sgn (t)=0; Work as t<0, Sgn (t)=-1.Then:
Wherein T
i≠ T
j '.
Order
represent r in (1) formula
gmolecule, the relation of (2) formula and (4) formula is substituted into:
Because the Sgn (X as i=j
i-X
j)=0, so:
Right
Exchange subscript i and j to obtain:
Obtained by (5) formula and (6) formula:
In like manner, make
represent r in (1) formula
gdenominator, the relation of (2) formula and (4) formula to be substituted into and the conversion being similar to (6) formula can obtain:
Then have:
Corresponding circuit of the present invention can be designed according to formula (9) formula.
With reference to shown in Fig. 1, the invention provides a kind of signal deteching circuit relevant based on Geordie, comprise two comparator arrays, subtracter array, two multiplier arrays, two adder trees, a divider and a register; Comparator, subtracter array are respectively the matrix (n is signal length) of a n × n, and each element on matrix is made comparisons computing and subtraction respectively; Multiplier array is n
2the multiplier of individual 2 inputs; Adder tree is a n
2the adder of individual input; Divider completes 2 input division arithmetics; The result of related operation deposited by register.
Concrete, signal x1 ... xn, y1 ... yn sends into corresponding comparator, subtracter array simultaneously respectively, wherein signal x1 ... xn's n has walked abreast
2secondary compare operation, i.e. sgn (xi-xj), wherein (i, j=1 ... n), signal y1 ... yn's n has walked abreast
2secondary compare operation and subtraction operation, i.e. sgn (yi-yj) and yi-yj, wherein (i, j=1 ... n), above course synchronization carries out, and n is signal length;
The comparison obtained, subtraction result sends into corresponding multiplier array simultaneously, synchronously completes n respectively
2secondary parallel 2 input multiply operation, i.e. sgn (xi-xj) (yi-yj) and sgn (yi-yj) (yi-yj), wherein (i, j=1 ... n);
The multiplication result obtained sends into corresponding adder tree simultaneously, synchronously completes n respectively
2the parallel addition operation of individual 2 inputs, namely
With
Wherein (i, j=1 ... n);
The addition results obtained is sent in 2 input dividers, completes
wherein (i, j=1 ... n);
The correlation result obtained is sent in register.
Based on the signal detecting method that Geordie is relevant, comprise step:
S1, signal x1 ... xn, y1 ... yn sends into corresponding comparator, subtracter array simultaneously respectively, wherein signal x1 ... xn's n has walked abreast
2secondary compare operation, i.e. sgn (xi-xj), wherein (i, j=1 ... n), signal y1 ... yn's n has walked abreast
2secondary compare operation and subtraction operation, i.e. sgn (yi-Yj) and yi-yj, wherein (i, j=1 ... n), above course synchronization carries out, and n is signal length;
The comparison that S2, step S1 obtain, subtraction result sends into corresponding multiplier array simultaneously, synchronously completes n respectively
2secondary parallel 2 input multiply operation, i.e. sgn (xi-xj) (yi-yj) and sgn (yi-yj) (yi-yj), wherein (i, j=1 ... n);
The multiplication result that S3, step S2 obtain sends into corresponding adder tree simultaneously, synchronously completes n respectively
2the parallel addition operation of individual input, namely
with
Wherein (i, j=1 ... n);
The addition results that S4, step S3 obtain is sent in 2 input dividers, completes
Wherein (i, j=1 ... n);
The correlation result that S5, step S4 obtain is sent in register.
The present invention is incorporated into signal transacting field relevant for Geordie first, in order to solve current convectional signals detection technique cannot impulse noise component well in process ambient noise on the problem of the impact of double-channel correlation analysis.In existing signal detection technique, the most conventional with matched filter.But its theoretical foundation based on ambient noise be simple additive white Gaussian noise hypothesis and reality should in system context not exclusively conform to.Wherein impulse noise component is composition common in ambient noise.Desirable matched filter because the instantaneous energy of impulsive noise is very big, in certain hour section, greatly reduces the signal to noise ratio of signal, even if so can also cannot avoid useful signal to be buried in noise by the output system maximum signal to noise ratio that can reach.Therefore when considering impulsive noise, improper already as standard using signal to noise ratio.
Coefficient correlation also can as the tolerance evaluating two paths of signals similarity degree in input as the strong instrument of in correlation analysis.Coefficient correlation classical in document is product moment correlation coefficient.But when this coefficient correlation be used in a road signal be clean signal templates and the signal of another road by noise pollution time Shortcomings part.Product moment correlation coefficient effectively can not be measured as one because paired pulses noise is very responsive.In order to reduce noise, the especially interference of impulsive noise, points out in document can use the rank information of corresponding data and not direct usage data value is dealt with.And known useful information should all be applied, information dropout is avoided to cause error.Thus, the definition that Geordie is correlated with inherently embodies such feature.
Contrasted by Monte Carlo Experiment that matched filter, product moment correlation coefficient and Geordie are relevant can illustrate that Geordie is correlated with the service behaviour mixed in process under the noise background of impulsive noise.As shown in Figure 2, in Fig. 2, (a) represents the signal that signal projector is launched, namely known signal templates to its schematic diagram.The signal sent entered transmission and was received by receiver, under perfect condition, the signal received should be completely the same with the waveform that transmits but the signal that there is certain time-delay K0 as shown in (b) in Fig. 2; But owing to there is various noise in environment, mainly white Gaussian noise and the impulsive noise that often occurs, what the actual signal that receiver receives was noise and signal superposes as shown in (c) in Fig. 2.In order to detect the time delay of Received signal strength, use known signal templates as scanning window as shown in (d) in Fig. 2, from the signal received, choosing the signal of one section of equal length and signal templates in order do correlation analysis and obtain correlation at every turn, finally judging that time point K0 corresponding to the maximum in all correlations is for wanting the position at the signal place detected as shown in (e) in Fig. 2.
Experimental design is as follows: (signal templates) Y that transmits is set to:
Its average and variance are respectively E (Y)=0 and Var (Yr)=1.Noise section is produced by mixed Gauss model:
(1-ε)N(0,σ
2)+εN(0,σ′
2),
The wherein probability that occurs in whole noise background of ε=0.02 indicating impulse noise, σ '=10
4> > σ indicating impulse noise.Received signal strength is useful signal and noise sum.Under this set point, the signal to noise ratio of Received signal strength is defined as
Monte Carlo Experiment number of times is set to 10000 times.Namely the 1000th time point that setting echo-signal is positioned at Received signal strength have k
0=1000.Experiment purpose is that can the various method of checking detect the useful signal be hidden in background noise under different signal to noise ratios.The schematic diagram of experiment as shown in Figure 1.Relevant experimental data is as shown in table 1.
SNR |
Matched filter |
Product moment correlation coefficient |
Geordie is correlated with |
0 |
748.20±461.72 |
753.62±455.13 |
999.98±0.89 |
-1 |
743.86±457.64 |
741.69±454.23 |
999.99±0.96 |
-2 |
757.11±457.24 |
749.62±452.87 |
999.99±1.06 |
-3 |
750.58±461.76 |
7S3.23±455.54 |
999.99±1.17 |
-4 |
756.80±456.89 |
749.51±452.75 |
999.97±1.63 |
-5 |
756.97±457.10 |
749.47±453.04 |
999.96±2.01 |
-6 |
750.91±461.86 |
753.33±455.27 |
1000.03±4.19 |
-7 |
756.89±456.90 |
749.66±452.73 |
999.87±6.35 |
-8 |
756.93±456.86 |
749.70±452.73 |
999.90±10.76 |
-9 |
751.90±462.03 |
753.08±455.56 |
999.99±15.72 |
-10 |
756.84±456.81 |
749.48±452.80 |
999.98±22.34 |
Table 1 contrast test data
Data display mode in table 1 is repeatedly Monte Carlo experiment " means standard deviation ".Experimental result shows, when containing impulsive noise composition in ambient noise, matched filter and product moment correlation coefficient lost efficacy substantially, and Geordie is correlated with shows its splendid robustness in containing the noise circumstance of pulse repetition, comprises very close to average and the less standard deviation of actual value.Which illustrating that Geordie is correlated with is a kind of effective tool carrying out input in containing the environment of impulse noise interference, and has splendid performance advantage compared with the method generally used at present.
The foregoing is only the preferred embodiments of the present invention; not thereby its scope of the claims is limited; every utilize specification of the present invention and accompanying drawing content to do equivalent structure or equivalent flow process conversion; directly or indirectly be used in the technical field that other are relevant, be all in like manner included in scope of patent protection of the present invention.